End User Request:

 

The end user was looking for a solution for the switch gear rooms at their factory. These rooms cool the power supplies for the machinery on the factory floor. End user had an existing unit that was 22 tons to cool this room off. 

 

The biggest complaint the end user has that the cooling units will break down and due to time and the labor to get the parts in, the factory line is down too long and then in turn, losing money. 

 

The end user is now looking to do a redundant system. They are also interested in saving energy as well. 

 

Current Equipment Setup Problems:

 

We found that when the load in these rooms were reaching there max, the current units worked quite well. The biggest problem with it was when the load was reduced the units would short cycle. The massive amount of short cycling wreaked havoc on the systems second compressor and was going out 1-2 times a year.

 

Johnstone-Contractor Partnered Solution:

 

We went ahead and visited the factory to see what we had for room and for cooling requirements. Both rooms need about 22 Tons of cooling at full load. One of the rooms we were quite limited in what we could do, due to height and clearance restrictions. The other switch gear room had a lot taller ceiling so we had a lot more to work with. 

 

With a little research we found that the current units capacities were not nominal capacities but they were all sensible heat capacities. This meant we had to design our new system to be able to handle this. After looking we decided to go the VRF route. Fujitsu VRF offered 8 ton air handlers and up to 16 ton in on chassis on the outdoor unit. We used the Fujitsu design simulator to simulate our conditions and to see how many units we needed. After looking we needed four 8 ton air handlers to get the capacity needed.

 

We were able to pair up two 8 ton air handlers to one 16 ton outdoor unit. This saved us roof space, which we did not have much in the location. Then all four air handlers were ducted together to create one 32 ton system. 

 

There are future plans to take care of specialty rooms within the factory as well. Taking over where low ambient controlled RTUS are failing. 

 

See Pictures Below:

 

As you can see, we did not have a lot of room to work with, but being able to go up to 1.2"wc of static pressure gave us the ability to fight against the small duct work. 

 

 

 

 

Here is a picture of the 16 ton outdoor units